226 MORPHOLOGY AND EVOLUTION
duct, artery, and vein have their usual arrangement on entering it. The right and left fissures almost reach to its two extremities. The umbilical fissure extends for
nearly 2 in. from the anterior border; thence to the
portal fissure the round ligament is buried beneath the hepatic substance joining the right and left central lobes.
The Spigelian lobe is small but conspicuous, narrow from before backwards, forming a prominent transverse ridge, continued into a trihedral free process, projecting to the left. Of nearly the same size is the caudate lobe> continuous with the Spigelian on the left, an<J passing as a ridge on to the under surface of the right lateral lobe, close to its posterior border, marked off from it anteriorly by a deep groove, and terminating in a pointed apes, free for the distance of one inch. This is separated from the right lateral lobe posteriorly by the great fossa for the vena cava, which fills the fossa, and is not bridged over by any hepatic substance.
The posterior part of the right lateral lobe is very little developed, so that the caudate lobe is unusually posterior in position. The distance from the left apex of the Spigelian lobe to the right apes of the caudate lobe is 6 in.; from the latter point to the margin of the right lateral lobe is 1J in. The gall-bladder had been removed from the specimen before it came under examination.
The pancreas is arranged on the same plan as in Man, and in some specimens a process passes up alongside the portal vein. The duct joins the common bile duct, and the common opening may lie on the summit of a bile papilla.